Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7882045 | Acta Materialia | 2014 | 13 Pages |
Abstract
The I1 intrinsic stacking fault energy (I1 SFE) serves as an alloy design parameter for ductilizing Mg alloys. In view of this effect we have conducted quantum-mechanical calculations for Mg15X solid-solution crystals (XÂ =Â Dy, Er, Gd, Ho, Lu, Sc, Tb, Tm, Nd, Pr, Be, Ti, Zr, Zn, Tc, Re, Co, Ru, Os, Tl). We find that Y, Sc and all studied lanthanides reduce the I1 SFE and render hexagonal closed-packed (hcp) and double hcp phases thermodynamically, structurally and elastically similar. Synthesis, experimental testing and characterization of some of the predicted key alloys (Mg-3Ho, Mg-3Er, Mg-3Tb, Mg-3Dy) indeed confirm reduced I1 SFEs and significantly improved room-temperature ductility by up to 4-5 times relative to pure Mg, a finding that is attributed to the higher activity of non-basal dislocation slip.
Related Topics
Physical Sciences and Engineering
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Authors
S. Sandlöbes, Z. Pei, M. Friák, L.-F. Zhu, F. Wang, S. Zaefferer, D. Raabe, J. Neugebauer,